40842409 has 4 divisors (see below), whose sum is σ = 41217220. Its totient is φ = 40467600.

The previous prime is 40842397. The next prime is 40842427. The reversal of 40842409 is 90424804.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35366809 + 5475600 = 5947^2 + 2340^2 .

It is a cyclic number.

It is not a de Polignac number, because 40842409 - 2⁹ = 40841897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40842479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 187242 + ... + 187459.

It is an arithmetic number, because the mean of its divisors is an integer number (10304305).

Almost surely, 2^40842409 is an apocalyptic number.

It is an amenable number.

40842409 is a deficient number, since it is larger than the sum of its proper divisors (374811).

40842409 is a wasteful number, since it uses less digits than its factorization.

40842409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374810.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 40842409 is about 6390.8066001093. The cubic root of 40842409 is about 344.3793616618.

The spelling of 40842409 in words is "forty million, eight hundred forty-two thousand, four hundred nine".